指定的初始化向量 (IV) 與此算法的塊大小不匹配

Question

   public static string GenerateKey()
   {
        AesCryptoServiceProvider aesCrypto = (AesCryptoServiceProvider)AesCryptoServiceProvider.Create();

        // Use the Automatically generated key for Encryption. 
        return ASCIIEncoding.ASCII.GetString(aesCrypto.Key);
    }

    static void EncryptFile(string sInputFilename, string sOutputFilename, string sKey)
    {
        FileStream fsInput = new FileStream(sInputFilename, FileMode.Open, FileAccess.Read);

        FileStream fsEncrypted = new FileStream(sOutputFilename, FileMode.Create, FileAccess.Write);
        AesCryptoServiceProvider AES = new AesCryptoServiceProvider();
        // Sets the appropriate block size for the AES Encryption Method
        AES.BlockSize = 128;
        AES.Key = ASCIIEncoding.ASCII.GetBytes(sKey);
        AES.IV = ASCIIEncoding.ASCII.GetBytes(sKey);
        ICryptoTransform aesencrypt = AES.CreateEncryptor();
        CryptoStream cryptostream = new CryptoStream(fsEncrypted, aesencrypt, CryptoStreamMode.Write);

        byte[] bytearrayinput = new byte[fsInput.Length];
        fsInput.Read(bytearrayinput, 0, bytearrayinput.Length);
        cryptostream.Write(bytearrayinput, 0, bytearrayinput.Length);
        cryptostream.Close();
        fsInput.Close();
        fsEncrypted.Close();
    }

    static void DecryptFile(string sInputFilename, string sOutputFilename, string sKey)
    {
        AesCryptoServiceProvider AES = new AesCryptoServiceProvider();
        //A 64 bit key and IV is required for this provider.
        //Set secret key For DES algorithm.
        AES.Key = ASCIIEncoding.ASCII.GetBytes(sKey);
        //Set initialization vector.
        AES.IV = ASCIIEncoding.ASCII.GetBytes(sKey);

        //Create a file stream to read the encrypted file back.
        FileStream fsread = new FileStream(sInputFilename, FileMode.Open, FileAccess.Read);
        //Create a DES decryptor from the DES instance.
        ICryptoTransform aesdecrypt = AES.CreateDecryptor();
        //Create crypto stream set to read and do a 
        //DES decryption transform on incoming bytes.
        CryptoStream cryptostreamDecr = new CryptoStream(fsread, aesdecrypt, CryptoStreamMode.Read);
        //Print the contents of the decrypted file.
        StreamWriter fsDecrypted = new StreamWriter(sOutputFilename);
        fsDecrypted.Write(new StreamReader(cryptostreamDecr).ReadToEnd());
        fsDecrypted.Flush();
        fsDecrypted.Close();
    }

我在 EncryptFile 方法的這一行中得到了標題中列出的異常。

AES.IV = ASCIIEncoding.ASCII.GetBytes(sKey);

我直接在該行之前設置了 BlockSize，並且我確定 AES 應該使用 16 字節的塊大小，那么我該怎么做才能讓它工作呢？ 我不確定為什么代碼仍然存在塊大小問題。

注意：我只是在嘗試我在網上找到的一些示例，這並不意味着是一個鎖緊的 AES 實現，只是我想開始工作，以便我可以繼續了解該算法。

謝謝你的幫助。

Answer 1

IV 必須與塊大小完全相同，在 AES 的情況下為 16 個字節。